https://www.vantaanenergia.fi/en/about-us/projects/varanto-t...
Also this calculation probably assumes no baseload power imported from the grid, where means such as wind and tidal power work year-round and help offset the need for batteries.
Basically, you end up having to overbuild to crazy levels, or build insane amounts of battery storage, which only gets used a few days a year.
The second point is that the distribution has a long tail, especially when we consider the possibility of multiple independent incidents overlapping in time, to the point where it becomes infeasible to suppose that we could be prepared to continue operating as if nothing had happened in all conceivable scenarios, regardless of how accurately we could predict their likelihood.
Things in the US are a bit more of a mixed bag, for better or worse, but there have been studies done that suggest that you can get very high renewables levels cost effectively, but not to 100% without new technology (eg “clean firm” power like geothermal, new nuclear being something other than a clusterfumble, long-term storage like iron-air batteries, etc etc etc).
Also, if solar ends up much cheaper than wind there's going to be need for seasonal energy storage, which could be considerably more than 2% at high latitude. Batteries are unsuitable for this.
This would also need some sort of turbine to convert back to electrical energy.
It'll be some combination of demand management (which isn't nearly as horrifying as people make it out to be), pumped hydro, long-duration batteries like iron-air, but also possibly burning hydrogen or hydrogen-derived synthetic fuels (produced by electrolysis when hydrogen is abundant) and/or biofuels in turbines.